Micro-electromechanical (“MEMS”) components and processes are used for a wide variety of different devices. For example, among other things, they are commonly used for producing accelerometers to detect acceleration, pressure sensors to detect pressure, power scavengers to accumulate power, and as microphones to capture acoustic signals.
MEMS capacitive microphones in particular have found a wide variety of different uses, such as in consumer electronics (e.g., cameras), smart phones and personal computers. This wide use is due in part to their higher stability and smaller size than traditional condenser microphones. As the technology improves, there is an increasing demand to enhance acoustic quality—in particular, higher sensitivity. In general, the dynamic range of a microphone is limited at the upper end by total harmonic distortion and at the lower end by its noise floor.